One of the sources of the
user-friendliness of the general CHSP formalism as
described by Scholtz et al [1]}
is that once we put, for simplicity, \(N_{}= 1\) ,
we just have to consider
the doublet
\(\lbrace {\cal H}_{math},{\cal H}_{phys}\rbrace \ = \ \lbrace {\cal R}_{1},{\cal R}_{0}\rbrace \,\) 
